The present invention generally refers to the creation of sterile or substantially sterile conditions for handling fluids for medical purposes.
In particular, the present invention refers to a connecting device for a medical system comprising a first subsystem having a first connection portion, and a second subsystem having a second connection portion, at least one of the subsystems containing a fluid, the connecting device being adapted to connect the subsystems to each other to permit transport of the fluid from at least one of the subsystem to the other subsystem, the device comprising a container enclosing an inner space, the container being adapted to receive the first connection portion and the second connection portion in the inner space.
Further, the present invention refers to a medical system comprising: a first subsystem having a first connection portion; a second subsystem having a second connection portion, at least one of the subsystems containing a fluid; and a connecting device being adapted to connect the subsystems to each other to permit transport of the fluid from at least one of the subsystem to the other subsystem, the connecting device comprising a container enclosing an inner space, the container being adapted to receive the first connection portion and the second connection portion in the inner space.
Still further, the present invention refers to a method for connecting in a medical system a first subsystem having a first connection portion and a second subsystem having a second connection portion to each other.
In the medical field, there are numerous situations where a fluid is to be transported from one subsystem to another subsystem during sterile conditions for preventing contamination of the fluid or any one of the subsystems. According to a first possible application of the present invention, the first subsystem may be a system for supplying infusion liquid to the blood system of a patient. A second application of the present invention may be the transfer of blood products or the transfer of blood from the blood system of an individual to the blood system of another individual, either directly between the individual or via any system for storing blood. Further applications of the present invention may include any supply of medical fluids into the body of an individual. A common aspect of these applications is that one of the subsystem is a biological system, such as the blood system of an individual. However, the present invention is also applicable to the transport of a fluid between two non-biological subsystems, for instance during the manufacture, cleaning, processing or treating of biological fluids of medical fluids, and during cleaning, processing or treating of biological fluids.
In the following, the present invention will be described in connection with dialysis, which is an important application of the invention. However, the invention is not restricted to this application, but may be applied to other fields as defined above.
There are two major dialysis therapies used today, namely haemodialysis and peritoneal dialysis. Haemodialysis is often performed three times a week for each patient during a respective treatment period of about four hours. Haemodialysis is normally carried out at clinics, hospitals or similar institutions, whereby the patient is bound to the dialysis apparatus, and thus in principal prevented from taking part in any other activity during the treatment procedure.
Peritoneal dialysis can be carried out at home and by the patient himself, who can operate the equipment required for the performance of the treatment. Peritoneal dialysis is initiated by the patient who connects himself via a catheter introduced into the abdominal cavity to a dialysis container set comprising a waste bag and a bag with dialysis liquid. In a first step the liquid present in the abdominal cavity is discharged to the waste bag, and then the new dialysis liquid is supplied from the dialysis liquid bag into the abdominal cavity. When the dialysis liquid has been introduced, which takes about half an hour, the patient disconnects himself. The dialysis treatment then takes place during a certain time period during which the patient can take part in other activities and in principal live a normal life. After said time period, the dialysis liquid has to be exchanged, whereby the patient connects himself for replacement of the dialysis liquid in the abdominal cavity with new dialysis liquid. These operations can be performed by the patient himself at any suitable place. Consequently, peritoneal dialysis has important advantages in that it increases the freedom of life for the patients, and can thus be a preferred treatment method.
There are, however, problems which prevent a continuing use of peritoneal dialysis and which make a change to haemodialysis necessary. These problems involve, for instance, inadequate dialysis and peritonitis. Investigations have been performed, which show that peritonitis is a major problem in connection with peritoneal dialysis. Peritonitis can occur due to various reasons, for instance, contamination due to contact with the surrounding air, contamination due to direct touching of the catheter by the patient himself, catheter related infections, etc. Contamination due to touch contact or air contact can occur during the connection and disconnection of the dialysis container set to the patient. During this connection and disconnection, there exist the risks of contamination of the catheter, for instance by the surrounding air, by direct contact with the skin of the patient or with the floor or any other surrounding object. If the catheter is contaminated, bacteria and other micro-organisms can find there way into the patient and cause peritonitis.
In British Medical Journal, Volume 288, 4 Feb. 1984, pages 353-356, it has been proposed to perform the connection of the patient to the dialysis container set by enclosing the conduit end portions in a flexible sterile bag containing a disinfectant liquid. This proposed method is, however, rather complicated since it includes a number of steps to be performed by the patient. The conduit end portions are to be introduced in the flexible bag vi openings, and then the openings have to be tighten around the conduits in order to provide a sealed inner space in the bag. In the bag there are two gauze pieces which are provided around the end portions for removing the caps and for sterilising the end portions before the connection.